Plamoqraph co



v. SPENCER, ARTIFICIAL TOOTH.

APPLICATION FILED 06114 1918.

1,317,832. Patented 0 I.7,1919.

THE COLUMBIA PLANOGRAPH co., WASHINGTON, n. c.

VERNON SPENCER, OF MOSMAN, NEAR SYDNEY, NEW SOUTH WALES, AUSTRALIA.

ARTIFICIAL TOOTH.

Specification of Letters Patent.

Patented Oct. 7, 1919.

Application filed October 14, 1918. Serial No. 257,983.

Australia, have invented certain new and useful Improvements in Artificial Teeth, of which the following is a specification.

The invention relates to artificial teeth and more particularly to detachable porcelain facings which are employed in connection with metal backing plates to build up bridge work.

The principal object of the invention consists in providing at the backing a depression to form a chamber and having an integral flange overhanging all sides of the inlet opening of said chamber, the headed pins of the facing being secured in said chamber by dentalcement.

In order that the invention may be readily understood, I will now refer to the drawings herewith which are on. an exaggerated scale for sake of clearness.

Figure 1 is a sectional elevation, and

Fig. 2 a transverse section of a pin tooth provided with my improved backing.

Figs. 3 and 4 are rear and front perspective views illustrating the backing.

The same numerals indicate the same parts.

5 is a porcelain tooth provided with the metal pins 6 which may be headed as shown or they may be the usual straight pins bent angularly. 7 is a thin metal backing having thereon a recess or chamber 8 in which the pins take and are secured therein by dental cement 9 of any suitable kind. Theentrance to the recess is preferably of slightly less cross sectional area than the recess itself in order to insure better retention of the cement and the pins embedded therein.

In removing a tooth so secured for the purpose of substituting another, the operation' can be readily performed with the usual dental instruments.

Preferably one end of the backing is bent over the edge of the tooth as at 10 and burnished forming a tip which takes the stress .of mastication, protecting the porcelain from injury, and strengthening the bite.

By soldering or forming a retainer on the backing it may be employed with vulcanite or other like composition plates.

I claim r In artificial teeth, a metal backing for a porcelain tooth having headed pins, said backing being depressed to form a chamber and having an integral flange overhanging all sides of the inlet opening of said chamher, the headed pins being secured in said chamber by dental cement, substantially as described. 1

In testimony whereof I have hereunto set my hand.

VERNON SPENCER.

Copies of this patent may be obtained for five cents each, by addressing the Gommissioner of Patents, Washington, D. 0." 

